Process for reacting an organic compound in the presence of a supported ruthenium catalyst

ABSTRACT

A process for the reaction of an organic compound in the presence of a catalyst comprising, as active metal, ruthenium alone or together with at least one Group Ib, VIIb, or VIIIb metal in an amount of from 0.01 to 30 wt %, based on the total weight of the catalyst, applied to a support, wherein from 10 to 50% of the pore volume of the support comprises macropores having a pore diameter in the range of from 50 nm to 10,000 nm and from 50 to 90% of the pore volume of the support comprises mesopores having a pore diameter in the range of from 2 to 50 nm, the sum of said pore volumes being 100%, and said catalyst as such.

The present invention relates to a process for reacting an organiccompound in the presence of a catalyst which comprises ruthenium andoptionally one or more further Group IB, VIIB, or VIIIB metals, appliedto a porous support, as active metal(s).

In one embodiment the present invention relates to a process for thereaction, preferably hydrogenation, of an aromatic compound in which atleast one hydroxyl group is attached to an aromatic core, wherepreferably at least one optionally substituted C₁-C₁₀- alkyl groupand/or at least one C₁-C₁₀-alkoxy group is attached to an aromatic corein addition to said at least one hydroxyl group. Furthermore,monoalkyl-substituted phenols are preferably used in the process of theinvention.

The mononuclear or polynuclear aromatic compounds are preferablyhydrogenated in the presence of the catalyst that is described herein toproduce the corresponding cycloaliphatic compounds, during which processthe hydroxyl group remains intact.

Cycloaliphatic alcohols, and particularly alkylcyclohexanols, areimportant intermediates for the preparation of various perfumes,medicines and other organic fine chemicals. The above cycloaliphaticalcohols are readily obtained by catalytic hydrogenation of thecorresponding aromatic precursors.

The method of preparing alkylcyclohexanols by catalytic hydrogenation ofthe corresponding alkylphenols is known. The hydrogenation ofalkylphenols to form the corresponding alkylcyclohexanols in thepresence of hydrogenation catalysts, particularly catalysts that areapplied to supports, has been described in many places.

The catalysts used are metallic rhodium, rhodium/platinum andrhodium/ruthenium alloys, and also ruthenium, palladium, or nickel oncatalyst supports. The catalyst supports used are carbon, bariumcarbonate, and, particularly, aluminum oxide.

PL 137,526 describes the hydrogenation of p-tert-butylphenol to formp-tert-butylcyclohexanol using a nickel catalyst.

DE-A 3,401,343 and EP 0,141,054 describe a process for the preparationof 2- and 4-tert-butylcyclohexanol from 2- and 4-tert-butylphenol bycatalytic hydrogenation. The hydrogenation is carried out in two stages,a palladium catalyst on a Al₂O₃ support being used in the first stageand a ruthenium catalyst on a Al₂O₃ support being used in the secondstage. The metal content on the support is from 0.1 to 5 wt.-%. Thesupports are not specified. The process is carried out under a pressureof 300 bar with recycling of the product, and there are preferablyobtained the cis-tert-butylphenols, during which process from 0.1 to0.5% of by-products are formed.

U.S. Pat. No. 2,927,127 describes a process for the preparation ofp-tert-butylcyclohexanol and esters thereof by catalytic hydrogenationof p-tert-butylphenol. The catalysts used are 5% of rhodium on carbon,5% of palladium on barium carbonate and 5% of ruthenium on carbon. Whenusing ruthenium on carbon the process has been carried out under apressure of from 70 to 120 bar and at a temperature of from 74° C. to93° C. The hydrogenation product obtained comprised 66% of cis-isomer.

DE-A 2,909,663 describes a process for the preparation ofcis-alkylcyclohexanols by catalytic hydrogenation of the correspondingalkylphenols. The catalyst used was ruthenium on a Al₂O₃ support. Theprocess was carried out under pressures of 40, 60, and 80 bar. Theproducts obtained were predominantly cis-alkylcyclohexanols, whilst theby-product obtained comprised from 0.1 to 1% of alkyl benzenes.

In a further embodiment the present invention relates to a process forthe reaction, preferably hydrogenation, of an aromatic compound in whichat least one amino group is attached to an aromatic core, wherepreferably at least one optionally substituted C₁-C₁₀ alkyl group and/orat least one C₁-C₁₀ alkoxy group is attached to an aromatic core inaddition to said at least one amino group. In particular,monoallyl-substituted amines are preferably used.

The mononuclear or polynuclear aromatic compounds are preferablyhydrogenated to the corresponding cycloaliphatic compounds in thepresence of the catalyst that is described herein, during which processthe amino group remains intact.

Cycloaliphatic amines, and particularly optionally substitutedcyclohexylamines and dicyclohexylamines, are used for the preparation ofage protectors for caoutchoucs and plastics materials, as anticorrosiveagents and also as intermediates for plant protectants and textileauxiliaries. Moreover cycloaliphatic diamines are used in themanufacture of polyamide and polyurethane resins and are also used ascuring agents for epoxy resins.

It is known to be possible to prepare cycloaliphatic amines by catalytichydrogenation of the corresponding mononuclear or polynuclear aromaticamines. The hydrogenation of aromatic amines to form the correspondingcycloaliphatic amines in the presence of hydrogenation catalysts,particularly catalysts that are applied to supports, has been describedin many places.

The catalysts used are for example Raney cobalt containing basicadditives (JP 43/3180), nickel catalysts (U.S. Pat. No. 4,914,239, DE805,518), rhodium catalysts (BE 739,376, JP 7,019,901, JP 7,235,424),and also palladium catalysts (U.S. Pat. No. 3,520,928, EP 501,265, EP53,818, JP 59/196843). In most cases, however, catalysts containingruthenium are used.

DE 2,132,547 describes a process for the hydrogenation of mononuclear orpolynuclear aromatic diamines to produce the correspondingcycloaliphatic amines which is carried out in the presence of asuspended ruthenium catalyst.

EP 67,058 describes a process for the preparation of cyclohexylamine bycatalytic hydrogenation of the corresponding aromatic amine. Thecatalyst used is ruthenium metal in a finely divided state on activatedaluminum pellets. After four recyclings the catalyst began to lose itsactivity.

EP 324,984 relates to a process for the preparation of a mixture ofoptionally substituted cyclohexylamine and optionally substituteddicyclohexylamine by hydrogenation of optionally substituted anilineusing a catalyst containing ruthenium and palladium on a support which,moreover, contains an alkaline reacting alkali metal compound acting asmodifier. A basically similar process is described in EP 501,265, wherethe catalyst contains niobic acid, tantalic acid, or a mixture of thetwo, as modifier.

U.S. Pat. No. 2,606,925 describes a process for the preparation of anaminocyclohexyl compound by hydrogenation of a corresponding aromaticcompound where a ruthenium catalyst is used, whose active catalyticcomponent is selected from elementary ruthenium, ruthenium oxides, andruthenium salts in which the ruthenium is present in the anion or in thecation. As revealed by the examples of said process, the catalyst isprepared and dried in a separate stage and is introduced into thereaction vessel after a relatively long drying time.

A further process for the preparation of cyclohexylamine is described inU.S. Pat. No. 2,822,392, and the main feature of this patentspecification involves the use of a specific reactor in which theaniline and hydrogen used as starting products are caused to react witheach other countercurrently.

U.S. Pat. No. 3,636,108 and U.S. Pat. No. 3,697,449 relate to thecatalytic hydrogenation of aromatic compounds containing nitrogen usinga ruthenium catalyst which additionally contains an alkali metalcompound acting as modifier.

Common to all of the above processes is the use of mesoporous supportshaving surface areas (BET) which are typically between 50 and more than1000 m²/g in order to achieve a high activity of the catalyst.

Furthermore, apart from the high cost of the catalyst, it has been foundto be a disadvantage, particularly during hydrogenation using arhodium-containing catalyst, that relatively large amounts of alkylbenzenes and other, unidentifiable compounds which are formed asdecomposition products or by-products during hydrogenation frequentlyoccur during such reactions. These by-products restrain working-up andpurification of the reaction product particularly whenalkylcyclohexanols are to be used, e.g., as perfumes or for thepreparation of perfumes. Furthermore, the activity of many catalystsused in the above processes declines rapidly, particularly when thehydrogenation is carried out for the acceleration of the reactionvelocity at relatively high temperatures.

In a further embodiment thereof, the present invention relates to aprocess for reacting, preferably hydrogenating, polymers having groupsto be reacted, preferably having nitrile groups by using a catalystcomprising ruthenium as described herein.

Processes for the hydrogenation of polymers comprising at least one unitto be hydrogenated are known as such. One group of polymers, which hasbeen used in the past particularly intensively as starting materials inprocesses for hydrogenating polymers are polymers comprising nitrilegroups. Also in the process according to the invention these polymersare preferably used leading to the corresponding polymers comprisingamino groups.

The polymers having amino groups as obtained by this process may be usedas e.g. branching agents, cross-linking agents or complexing agents,aming which as preferred applications for such polymers the papermanufacture, detergent industry, adhesives and cosmetics are exemplarilyto be mentioned.

In the past a plurality of systems for the reduction of polymerscomprising nitrile groups in order to obtain polymers comprising aminogroups have been described. Among those also the hydrogenation by meansof hydrogen has to be mentioned besides the reduction using complexmetal hydrides, as e.g. described in the German patents DE 1 226 303 andDE 2 905 671.

The hydrogenation by means of hydrogen is significantly less expensiveand—in contrast to the reduction by means of complex metal hydrides—onlycatalytic amounts of a metal containing component is required, which haseconomical and ecological advantages.

In the past, the hydrogenation by means of hydrogen was carried outeither homogeneously catalyzed or heterogeneously catalyzed.

The homogeneous catalysis is chemically elegant, but the separation ofthe catalyst is significantly more elaborate compared to theheterogeneous catalysis. The use of a homogeneous catalyst isparticularly disadvantageous in catalytic processes using polymers,since a distillative separation of the polymeric product from thecatalyst is not possible. If the polymeric product is to be separatedfrom the homogeneous catalyst by crystallization or precibitation,repeated crystallization is required, since inclusions of the catalystoccur, which leads to prolonged duration and higher costs.

Problems attributed to the separation of the catalyst do not occur inheterogeneous-catalyzed reactions. However, the knownheterogeneous-catalyzed processes for the hydrogenation of polymerscomprising nitrile groups, as carried out mostly by using metal solidbed catalysts according to Raney often only lead to poor yields andselectivities.

U.S. Pat. No. 2,456,428 describes the hydrogenation ofpoly(acrylonitrile), poly(methacrylonitrile) and similar polymers. Afterthe hydrogenation in the presence of Raney nickel as a catalyst,non-reacted polymer has to be separated prior to the further work-up.Conclusively, the reaction described therein did not run quantitatively,the yields achieved by said process are poor.

According to U.S. Pat. No. 3,122,526, which relates to the hydrogenationof cyano-ethylated poly(acrylonitrile) by using Raney nickel as acatalyst, also only moderate yields of the corresponding amine of below10% are obtained.

U.S. Pat. No. 2,585,583 describes the hydrogenation of copolymers ofbutadiene and acrylonitrile and methacrylonitrile, respectively, byusing suspension hydrogenation catalysts. The U.S. Pat. No. 2,647,146describes the hydrogenation of butadiene oligomers having nitrile endgroups by using a mixture of two suspension catalysts (Pd on carbon andNi on diatomaceous earth). According to these two processes therespectively used catalysts have to be separated from the reactionsolution by filtration.

Summarizing the above, it has to be stated that the hydrogenation ofpolymers comprising nitrile groups in order to obtain polymerscomprising amino groups is known as such, however, good yields ofpolymers comprising amino groups have been up to now only obtained byusing suspension catalysts. However, these have to be separated from thereaction solution by filtration and may not be used in a solid bedreactor.

In a further embodiment thereof, the present invention relates to aprocess for the hydrogenation of polymers containing C—C multiple bondsin the presence of a catalyst containing ruthenium or palladium andoptionally one or more other Group Ib, VIIb, or VIIIb metals as activemetals on a porous support.

Polymers having C—C multiple bonds, such as polybutadine,poly(styrene-co-butadiene)s, poly(styrene-co-isoprene)s,poly(acrylonitrile-co-butadiene)s, etc. have great industrialsignificance, particularly for applications involving food packaging,impact-resistant materials, adhesives, etc. Their saturated regions makethese polymers sensitive to thermal and oxidative degradation, with theresult that they usually show poor resistance to atmosphericdegradation. Polymers in which the C—C multiple bonds, such as C—Cdouble bonds, have been hydrogenated, usually show a distinctimprovement in stability.

In the past, a large number of homogeneous and heterogeneous catalystshas been described for this hydrogenation.

Processes involving hydrogenation using homogeneous catalysts, asdescribed for example in U.S. Pat. Nos. 3,595,295, 3,595,942, 3,700,633and 3,810,957, exhibit a high degree of selectivity toward thehydrogenation of unsaturated C—C bonds, i.e. any aromatic regionspresent in said polymers are left virtually unhydrogenated. Suchprocesses suffer however from the drawback that the catalyst used indissolved form can be separated from the desired product only by usingelaborate working-up stages, which increases the process costs to anundesirable extent.

When hydrogenation is carried out using heterogeneous catalysts, theproblem of catalyst separation does not occur. Such catalyst systems, asdescribed in, e.g., U.S. Pat. No. 3,333,024 and Belgian PatentApplication No. 871,348, exhibit distinctly less selectivity thanhydrogenations carried out using homogeneous catalysts, that is to say,any aromatic regions present in the polymers are also hydrogenated to asignificant extent.

For this reason heterogeneous catalysts have in the past been soughtwhich are capable of selectively hydrogenating ethylenic double bonds inpolymers.

Thus GB-A 2,061,961 describes a suspension catalyst consisting of 5%rhodium on activated charcoal, but this can be used for thehydrogenation of triple-block poly(styrene-co-butadiene)s only up to amolecular weight of 60,000.

U.S. Pat. No. 4,560,817 describes selective hydrogenation ofpoly(styrene-co-butadiene)s using a catalyst partially poisoned by analkali metal or alkaline earth metal alkoxide, in which process thepolymer is caused to react, during hydrogenation, with a mixture ofhydrogen and ammonia or an organic amine. In order to achieve sufficientactivity, the hydrogenation temperatures are near the decompositiontemperature of the polymers.

A catalyst consisting of a macroporous support material to which a GroupVIIIB metal is applied, which can be used for the hydrogenation ofcarbon-carbon double bonds, is described in U.S. Pat. No. 5,110,779.Ninety percent of the pores that are present in the support material ofthe catalyst described in said reference posses a diameter of greaterthan 100 nm. The ratio of the surface area of the metal to that of thesupport is from 0.07 to 0.75:1. In said patent specificationparticularly emphasis is placed on the large surface area of the metalcompared with that of the support, and this is stated to be surprising,since such a catalyst still possesses high activity.

Furthermore, the present invention relates in particular to a processfor the reaction, preferably hydrogenation, of an organic compoundcomprising at least one C═O-group, such as a ketone, aldehyde, acarboxylic acid or a derivative thereof, or a mixture of two or morethereof.

It is thus an object of the present invention to provide a process forthe reaction, preferably hydrogenation, of an organic compound asdefined above where very high yields or almost quantitative conversionsare achieved.

Another object of the invention is to provide such a process in whichonly a minimum content of by-products or decomposition products isformed during hydrogenation.

It should also be possible to carry out the process operating at highspace velocities and with long on-stream times at an extremely highturnover number, the corresponding hydrogenation products being obtainedin high yield and purity.

One or more of the above objects is/are achieved with a process for thereaction, preferably hydrogenation of an organic compound in thepresence of a catalyst comprising, as active metal, ruthenium alone ortogether with at least one Group Ib, VIIb, or VIIIb metal in an amountof from 0.01 to 30 wt %, based on the total weight of the catalyst,applied to a support, wherein from 10 to 50% of the pore volume of thesupport comprises macropores having a pore diameter in the range of from50 nm to 10,000 nm and from 50 to 90% of the pore volume of the supportcomprises mesopores having a pore diameter in the range of from 2 to 50nm, the sum of said pore volumes being 100%.

In another embodiment, the present invention relates to a process forthe reaction, preferably hydrogenation of polymers containing C—Cmultiple bonds in the presence of a catalyst comprising, as activemetal, ruthenium alone or together with at least one Group Ib, VIIb, orVIIIb metal in an amount of from 0.01 to 30 wt %, based on the totalweight of the catalyst, applied to a support, or in the presence of acatalyst comprising, as active metal, palladium alone or together withat least one Group Ib, VIIb, or VIIIb metal in an amount of from 0.01 to30 wt %, based on the total weight of the catalyst, applied to asupport, wherein the catalysts are respectively characterized in thatfrom 10 to 50% of the pore volume of the support comprises macroporeshaving a pore diameter in the range of from 50 nm to 10,000 nm and from50 to 90% of the pore volume of the support comprises mesopores having apore diameter in the range of from 2 to 50 nm, the sum of said porevolumes being 100%.

The above objects and any other objects of the invention are achieved bythe processes for reaction, preferably hydrogenation as described in thesub-claims. One special advantage of the process of the invention isthat very good results are attained when using only small metal contentsin the catalyst.

Furthermore, the process of the invention exhibits high turnover numbersat high space velocities over long catalyst on-stream times. The spacevelocity is the space-time yield of the process, i.e. the weight of theeduct that is caused to react per unit of time per unit weight of thecatalyst present. The “on-stream time” is the time during which thatweight of educt is caused to react which can just be catalyzed by thecatalyst without the latter suffering any change in properties andwithout the properties of the product being significantly modified.

Furthermore, the present invention relates to the catalyst as definedherein, i.e. a catalyst comprising, as active metal, ruthenium alone ortogether with at least one Group Ib, VIIb, or VIIIb metal in an amountof from 0.01 to 30 wt %, based on the total weight of the catalyst,applied to a support, or a catalyst comprising, as active metal,palladium alone or together with at least one Group Ib, VIIb, or VIIIbmetal in an amount of from 0.01 to 30 wt %, based on the total weight ofthe catalyst, applied to a support, wherein the catalysts arerespectively characterized in that from 10 to 50% of the pore volume ofthe support comprises macropores having a pore diameter in the range offrom 50 nm to 10,000 and from 50 to 90% of the pore volume of thesupport comprises mesopores having a pore diameter in the range of from2 to 50 nm, the sum of said pore volumes being 100%.

COMPOUNDS

The term “organic compound” as used within the present inventioncomprises all organic compounds including low molecular weight(monomeric) and polymeric organic compounds which may be catalyticallyreacted, in particular those which exhibit groups which are treatablewith hydrogen, such as C—C-double or C—C-triple bonds. This termcomprises low molecular weight organic compounds as well as polymers.“Low molecular weight organic compounds” are compounds having amolecular weight of below 500. The term “polymer” is definded asrelating to molecules having a molecular weight of higher than about500.

The present invention relates particularly to a process for reacting anorganic compound in the present of a catalyst as defined herein, whereinthe reaction is a hydrogenation, dehydrogenation, hydrogenolysis,aminating hydrogenation or dehalogenation, more preferably ahydrogenation.

In particular, organic compounds having one or more of the followingstructural units may be used.

The process of the invention is particularly suitable for reacting,preferably hydrogenating, an organic compound which is selected from thegroup consisting of an aromatic compound in which at least one hydroxylgroup is bonded to an aromatic ring, an aromatic compound in which atleast one amino group is bonded to an aromatic ring, a ketone, analdehyde, a carboxylic acid or a derivative thereof, a polymercomprising at least one C—C double bond, a polymer comprising at leastone C═O-group, a polymer comprising at least one C≡N-group, and amixture of two or more thereof.

Within the process of the invention organic compounds comprising unitsof different structures, as defined above, may be reacted, such asorganic compounds which exhibit C—C-multiple bonds and carbonyl groups,since the catalyst used within the process of the invention are capableto first selectively hydrogenate one of the two groups, i.e. to achievea hydrogenation of these groups from about 90 to 100%, while at firstthe other groups are reacted, preferably hydrogenated, to an extent ofless than 25% and in general 0 to about 7%. Generally, first theC—C-multiple bond and subsequently the C═O-group are reacted, e.g.hydrogenated, respectively.

The term “aromatic compound in which at least one hydroxyl group isbonded to an aromatic ring” or “aromatic compound in which at least oneamino group is bonded to an aromatic ring” means all compounds whichhave a unit of the structure (I):

where R is a hydroxyl group or an amino group.

If, in the process of the present invention, use is made of aromaticcompounds in which at least one hydroxyl group and also at least oneunsubstituted or substituted C₁-C₁₀-alkyl radical and/or C₁-C₁₀-alkoxyradical is bonded to an aromatic ring, the resulting isomer ratio of cisto trans products can be varied within a wide range, depending on thereaction conditions (temperature, solvent). Furthermore, the compoundsobtained can be processed further without further purification steps,since the formation of alkylbenzenes is virtually completely avoided.

Like the above-described compounds in which at least one hydroxyl groupis bonded to an aromatic ring, aromatic compounds in which at least oneamino group is bonded to an aromatic ring can also be hydrogenated bythe process of the present invention to give the correspondingcycloaliphatic compounds with high selectivity. For the aminesadditionally substituted by a C₁-C₁₀-alkyl radial and/or C₁-C₁₀-alkoxyradical, what has been said above regarding the ratio of the cis andtrans isomers also apples.

In particular, this embodiment virtually completely avoids the formationof deamination products such as cyclohexanes or partially hydrogenateddimerization products such as phenylcyclohexylamines.

In detail, the following compounds may be reacted with the process ofthe invention:

Aromatic Compounds in Which at Least One Hydroxyl Group is Bonded to anAromatic Ring

Aromatic compounds in which at least one hydroxyl group and preferablyalso at least one unsubstituted or substituted C₁-C₁₀-alkyl radicaland/or alkoxy radical is bonded to an aromatic ring can be reacted,preferably hydrogenated, by means of the process of the presentinvention to give the corresponding cycloaliphatic compounds, with italso being possible to use mixtures of two or more of these compounds.The aromatic compounds used can be monocyclic or polycyclic aromaticcompounds. The aromatic compounds contain at least one hydroxyl groupbonded to an aromatic ring; the simplest compound of this group isphenol. The aromatic compounds preferably have one hydroxyl group peraromatic ring and can be substituted on the aromatic ring or rings byone or more alkyl and/or alkoxy radicals, preferably C₁-C₁₀-alkyl and/oralkoxy radicals, particularly preferably C₁-C₁₀-alkyl radicals, inparticular methyl, ethyl, propyl, isopropyl, butyl, isobutyl andtert-butyl radicals; among the alkoxy radicals, preference is given toC₁-C₈-alkoxy radicals such as the methoxy, ethoxy, propoxy, isopropoxy,butoxy, isobutoxy and tert-butoxy radicals. The aromatic ring or ringsand also the alkyl and alkoxy radicals may be unsubstituted orsubstituted by halogen atoms, in particular fluorine atoms, or othersuitable inert substituents.

Preferably, the compounds which can be reacted, preferably hydrogenated,according to the present invention have at least one, preferably fromone to four, in particular one, C₁-C₁₀-alkyl radical which is preferablylocated on the same aromatic ring as the hydroxyl group or groups.Preferred compounds are (mono)alkylphenols, where the alkyl radical canbe in the o, m or p position relative to the hydroxyl group. Particularpreference is given to trans-alkylphenols, also known as 4-alkylphenols,where the alkyl radical preferably has from 1 to 10 carbon atoms and is,in particular, a tert-butyl radical. Preference is given to4-tert-butylphenol. Polycyclic aromatic compounds which can be usedaccording to the present invention are, for example, β-naphthol andα-naphthol.

The aromatic compounds in which at least one hydroxyl group andpreferably also at least one unsubstituted or substituted C₁-C₁₀-alkylradical and/or alkoxy radical is bonded to an aromatic ring can alsohave a plurality of aromatic rings which are linked via an alkyleneradical, preferably a methylene group. The alkylene group, preferablymethylene group, which forms the linkage can have one or more alkylsubstituents which can be C₁-C₂₀-alkyl radicals and are preferablyC₁-C₁₀-alkyl radicals, particularly preferably methyl, ethyl, propyl,isopropyl, butyl or tert-butyl.

In these compounds, each of the aromatic rings can bear at least onebonded hydroxyl group. Examples of such compounds are bisphenols, whichare linked in the 4 position via an alkylene radical, preferably amethylene radical.

In the process of the present invention, particular preference is givento reacting a phenol substituted by a C₁-C₁₀-alkyl radical, preferablyC₁-C₆-alkyl radical, where the alkyl radical may be unsubstituted orsubstituted by an aromatic radical, or mixtures of two or more of thesecompounds.

In a further preferred embodiment of this process, p-tert-butylphenol,bis(p-hydroxyphenyl)dimethylmethane or a mixture thereof is reacted.

Aromatic Compounds in Which at Least One Amino Group is Bonded to anAromatic Ring

The process of the present invention also enables aromatic compounds inwhich at least one amino group is bonded to an aromatic ring to bereacted, preferably hydrogenated, to give the correspondingcycloaliphatic compounds, with mixtures of two or more of thesecompounds also being able to be used. The aromatic compounds can bemonocyclic or polycyclic aromatic compounds. The aromatic compoundscontain at least one amino group which is bonded to an aromatic ring.The aromatic compounds are preferably aromatic amines or diamines andcan be substituted on the aromatic ring or rings or on the amino groupby one or more alkyl and/or alkoxy radicals, preferably C₁-C₂₀-alkylradicals, in particular methyl, ethyl, propyl, isopropyl, butyl,isobutyl and tert-butyl radicals. Among the alkoxy radicals, preferenceis given to C₁-C₈-alkoxy radicals such as methoxy, ethoxy, propoxy,isopropoxy, butoxy, isobutoxy and tert-butoxy radicals. The aromaticring or rings and also the alkyl and alkoxy radicals can beunsubstituted or substituted by halogen atoms, in particular fluorineatoms, or other suitable inert substituents.

The aromatic compound in which at least one amino group is bonded to anaromatic ring can also have a plurality of aromatic rings which arelinked via an alkylene group, preferably a methylene group. The alkylenegroup, preferably methylene group, which forms the linkage can bear oneor more alkyl substituents which can be C₁-C₂₀-alkyl radicals and arepreferably C₁-C₁₀-alkyl radicals, particularly preferably methyl, ethyl,propyl, isopropyl, butyl, sec-butyl or tert-butyl.

The amino group bonded to the aromatic ring may be unsubstituted orsubstituted by one or two of the above-described alkyl radicals.

Particularly preferred compounds are aniline, naphthylamine,diaminobenzenes, diaminotoluenes and bi-p-aminophenylmethane or mixturesthereof.

Compounds Comprising C═O Groups

Within the process of the invention it is also possible to react, inparticular to hydrogenate, compounds comprising C═O groups, i.e. inparticular aldehydes, ketones, carboxylic acids and their derivatives,such as carboxylic acid esters, carboxylic acid halides and carboxylicanhydrides, and mixtures of two or more of the above-mentionedcompounds.

In particular aldehydes and ketones, preferably those having 1 to 20C-atoms, such as formaldehyde, acetaldehyde, propionaldehyde,n-butyraldehyde, valeraldehyde, caproaldehyde, heptaldehyde,phenylacetaldehyde, acrolein, crotonaldehyde, benzaldehyde, o-, m-,p-tolualdehyde, salicylic aldehyde, anisaldehyde, vanillin, zinnamicaldehyde, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone,2-hexanone, 3-hexanone, cyclohexanone, isophorone, methyl isobutylketone, mesityl oxide, acetophenone, propiophenone, benzophenone,benzalacetone, dibenzalacetone, benzalacetophenone, glycol aldehyde,glyoxal, 2,3-butandione, 2,4-pentandione, 2,5-hexandione,terephthalaldehyde, glutaraldehyde, diethylketone, methyl vinyl ketone,acetylacetone, 2-ethylhexanal, or mixtures of two ore more thereof, maybe used.

Furthermore, also polyketones, such as copolymers of ethylene and CO areused.

Furthermore, carboxylic acids and derivatives thereof, preferably thosehaving 1 to 20 C-atoms may be reacted. In particular, the following areto be mentioned:

Carboxylic acids, such as formic acid, acetic acid, propanoic acid,butanoic acid, iso-butanoic acid, n-valeric acid, pivalic acid, caproicacid, heptanoic acid, octanoic acid, decanoic acid, lauric acid,myristic acid, palmitic acid, stearic acid, acrylic acid, methacrylicacid, oleic acid, elaidic acid, linoleic acid, linolenic acid,cyclohexane carboxylic acid, benzoic acid, phenylacetic acid, o-, m-,p-toluylic acid, o-, p-chlorotenzoic acid, o-, p-nitrobenzoic acid,salicylic acid, p-hydroxybenzoic acid, anthranilic acid, p-aminobenzoicacid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipicacid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleicacid, fumaric acid, phthalic acid, isophthalic acid, teraphthalic acid,and mixtures of two or more thereof.

Carboxylic acid halides, such as the chlorides and bromides of theabove-mentioned carboxylic acids, in particular acetylchloride or-bromide, stearic acid chloride or -bromide and benzoic acid chloride or-bromide, which are dehalogenated.

Carboxylic acid esters, such as the C₁- to C₁₀-alkyl esters of theabove-mentioned carboxylic acids, particularly methyl formiate, aceticacid ester, butanoic acid butyl ester, dimethyl terephthalate, dimethyladipate, methyl (meth)acrylate, butyrolactone, caprolactone andpolycarboxylic acid esters, such as polyacrylic and polymethacrylic acidesters and copolymers and polyesters thereof, such aspoly(methyl(meth)acrylates); these esters are in particularhydrogenated, i.e. the esters are reacted to the corresponding acids andalcohols.

Carboxylic anhydrides, such as anhydrides of the above-mentionedcarboxylic acids, in particular acetic acid anhydride, propanoic acidanhydride, benzoic acid anhydride and maleic anhydride.

Carboxylic acid amides, such as amides of the above-mentioned carboxylicacids, such as formamide, acetamide, propionic amide, stearamide andterephthalamide.

In addition thereto, also hydroxy carboxylic acids, such as lactic,malic acid, tartaric acid or citric acid, or amino acids, such asglycine, alanine, proline and arginine may be reacted.

NITRILES

Furthermore, also nitriles, preferably aliphatic or aromatic mono ordinitriles, such as acetonitrile, propionitrile, butyronitrile, stearicacid nitrile, isocrotonic acid nitrile, 3-butinnitrile, 2,3-butadienenitrile, 2,4-pentadiene nitrile, 3-hexene-1,6-dinitrile,chloracetonitrile, trichloracetonitrile, lactic acid nitrile, phenolacetonitrile, 2-chlorbenzonitrile, 2,6-dichlorobenzonitrile,isophthalonitrile, particularly aliphatic alpha, omega-dinitriles, suchas succinonitrile, glutaronitrile, adiponitrile, pimelicnitrile andsuberic nitrile or aminonitriles, such as 4-amino butanoic acid nitrile,5-aminopentanoic acid nitrile, 6-aminohexanoic acid nitrile,7-aminoheptanoic acid nitrile and 8-aminooctanoic acid nitrile.

Furthermore, within the process according to the invention, thefollowing reactions may be carried out:

The hydrogenation of aromatic compounds, such as benzene, toluenes,xylols, naphthalines and substituted derivatives thereof, leading to thecorresponding alicylic compounds; the hydrogenation of alkenes oralkines, such as ethylene, propylene, 1-, 2-butene, 1-, 2-, 3- and4-octene, butadiene, and hexatriene leading to the correspondingalkanes; the hydrogenation of nitroalkanes, such as nitroethane,nitromethane, nitropropane and 1,1-dinitroethane leading to thecorresponding amines; the hydrogenation of imines, such as quinoneimines, ketimines, ketene imines or aliphatic imines, such aspropioamine, hexane imine; the dehalogenation or organic compounds whichcontain halogen atoms, particularly of aromatic halogen-containingcompounds, such as chloro- and bromobenzene, bromo- and chlorotoluenesand chloro- and bromo xylols, also including compounds with more thanone halogen atoms substituted, may be used; the aminating hydrogenationof i.e. alcohols, such as vinyl alcohol.

Furthermore, within the process of the invention also oximes may bereacted or secondary amines may be prepared starting from ketones andprimary amines.

POLYMERS

The catalysts according to the invention may be also used for thehydrogenation, dehydrogenation, hydrogenolysis, aminating hydrogenationand dehalogenation of large molecules, preferably of polymers.

Accordingly, the present invention also relates to a process forreacting a polymer comprising at least one catalytically reactable groupin the presence of the above identified catalyst, wherein thehydrogenation of polymers comprising C═O-groups, such as polyesters ofdicarboxylic acids, unsaturated monocarboxylic acids, such aspoly(meth)acrylates, olefin/CO-copolymers or polyketones, and thehydrogenation of polymers comprising nitrile groups, such as copolymersof styrene and butadiene, copolymers of acrylonitrile and the aminatinghydrogenolysis of polyvinylalcohols and polyketones in the presence ofthe above-mentioned catalyst are preferred.

In particular, the present invention relates to a process for thehydrogenation of a polymer comprising at least one C═O-group or apolymer comprising at least one C≡N-group.

The term “polymer comprising at least one catalytically reactable group”relates to all polymers comprising such groups, in particular topolymers comprising units having the structures (I) to (VIII), asdefined above with respect to the monomeric compounds, or a halogenatom. Needless to say that the referenced polymers comprise therespective unit at least once and that also one or more units of two ormore of said structures may be present in the polymer reacted accordingto the invention.

The average molecular weight of the polymers to be reacted within theprocess of the invention is generally about 500 to about 500000,preferably about 1000 to about 100000 and more preferably about 1000 toabout 50000. It is, however, possible to also react polymers having ahigher molecular weight of up to one or several millions. If polymerscomprising at least one C—C-multiple bond, i.e. polymers comprisingrepeating units of the above defined structures (I) and (II) arereacted, these generally exhibit a weight average molecular weight offrom about 5000 to about about 1000000, preferably from about 50000 toabout 500000 and more preferably from about 150000 to about 500000.

It is preferred to use polymers containing olefinic double bonds, and itis further preferred to use polymers containing diene units andcopolymers containing vinylaromatic units and diene units. Within thisreaction besides the catalyst comprising ruthenium as the active metal,also the catalyst comprising palladium as the active metal may be used,while for the other reactions described herein preferably the catalystcomprising ruthenium as the active metal is used. It has to be noted inthis respect that besides Ru and Pd also the herein defined Group Ib,VIIb, or VIIIb metals, which are of course different from Ru and Pd,respectively, may be used.

Common diene units include all conventional polyunsaturated monomerscontaining from three to twelve carbon atoms, butadiene being preferred.

Copolymers to be hydrogenated may contain recurring units in random,block, or tapered distribution.

Aromatic monomers which may be present in the polymers to behydrogenated in the process of the invention includemonovinyl-substituted and polyvinyl-substituted aromatic compounds, thepreferred monomers being styrene, alpha-methyl styrene, acrylonitrile,methacrylonitrile, and divinyl benzene. Furthermore, mixtures ofvinylaromatic and/or diolefin monomers, optionally together withconventional olefinic monomers, can be present in the polymers to behydrogenated.

As examples for polymers which are to be reacted, preferablyhydrogenated, with the process of the invention, the following are to bementioned:

Polymers having C—C-double bonds, e.g. polybutadienes, such aspoly(2,3-dimethylbutadiene), polyisoprene, polyacetylenes andpolycylopenta- and -hexadiene; polymers having C—C-triple bonds, such aspolydiacetylenes; polymers having aromatic groups, such as polystyrene,terpolymers of acrylonitrile, butadiene and styrene, and copolymers ofstyrene and acrylonitrile; polymers having C—N-triple bonds, such aspolyacrylonitrile, polyacrylonitrile-copolymers with e.g. vinylchloride, vinylidene chloride, vinyl acetate or (meth)acrylic acidesters or mixtures of two or more thereof as comonomers; polymers havingC—O-double bonds, such as polyesters, polyacrylamides, poly(acrylicacids), polyurea and polyketones; polymers having C—S-double bonds, suchas polysulfones and polyethersulfones; halogen-containing polymers, suchas poly(vinyl chloride) and poly(vinylidene chloride); and polymerscontaining nitro groups, which may be obtained by nitration of e.g.polyolefins by means of polymer analogous reactions.

Examples for polymers being preferably used within the present inventioninclude polyisoprene, polybutadiene, ethylene/CO-copolymers,propylene/CO-copolymers, poly(methyl(meth) acrylate), polyterephthalate,polyadipate, styrene-butadiene-copolymers,acrylonitrile-butadiene-copolymers, acrylonitrile-styrene-copolymers,styrene-isoprene-styrene-triblockcopolymers,styrene-butadiene-styrene-triblockcopolymers andstyrene-butadiene-styrene-starblockcopolymers.

Generally, a complete reaction of the introduced educts is achieved.However, the reaction, preferably hydrogenation, may be also carried outin such a way that by suitably choosing temperature, e.g. H₂-pressureand H₂-amount only one kind of e.g. groups to be hydrogenated may bereacted, while the other kind of e.g. groups to be hydrogenated are nothydrogenated.

The process of the invention is particularly suitable for reacting,preferably hydrogenating, polymers comprising units of differentstructure, as defined above, e.g. a polymer comprising C—C-multiplebonds and C═O-groups and/or C≡N-groups, since the catalyst of thepresent invention is capable to first selectively react the C—C multiplebond, e.g. to achieve a hydrogenation of these groups of about 90 to100%, while at the same time the C═O-groups and/or C≡N-groups arereacted, e.g. hydrogenated to an extent of less than 25% and in general0 to about 7%.

Furthermore, the process of the invention is particularly suitable forthe hydrogenation of polymers of high molecular weight and containingboth C—C multiple bonds and aromatic groups, since the catalysts used inthe process of the invention are capable of achieving hydrogenation ofthe C—C multiple bonds, e.g. ethylenically unsaturated regions, to anextent of from 90 to 100%, whilst the aromatic regions are hydrogenatedto an extent of less than 25% and generally to an extent of from 0% to7%.

After finishing this reaction, preferably hydrogenation of theC—C-multiple bonds, it is of course possible to nearly quantitativelyreact, preferably hydrogenate, the other unsaturated groups beingpresent in the polymer, e.g. C═O-groups by further introducing hydrogen.

The process of the invention may be used for already isolated and livingpolymers.

CATALYSTS

The catalysts to be used in the process of the invention may be preparedon an industrial scale by applying ruthenium or palladium and optionallyat least one Group Ib, VIIb, or VIIIb metal to a suitable support.Application may be effected by impregnating the support material with anaqueous metal salt solution, such as a solution of a ruthenium orpalladium salt, by spraying an appropriate metal salt solution on to thesupport, or by any other suitable method. Suitable ruthenium orpalladium salts for the preparation of the ruthenium and palladium saltsolutions, and suitable salts of the said Group Ib, VIIb, and VIIIbmetals are the nitrates, nitrosylnitrates, halides, carbonates,carboxylates, acetylacetonates, chlorine complexes, nitrito complexes,or amine complexes of said metals, the nitrates and nitrosylnitratesbeing preferred.

In the case of catalysts that contain other metals in addition toruthenium or palladium, the metal salts or metal salt solutions can beapplied simultaneously or successively.

The supports coated or impregnated with the solution of ruthenium salt,palladium salt, or metal salt are then dried, the preferred temperaturesbeing from 100° C. to 150° C. If desired, these supports can be calcinedat temperatures ranging from 200° C. to 600° C., preferably from 350° C.to 450° C. The coated supports are then activated by treatment in astream of gas containing free hydrogen at temperatures ranging from 30°C. to 600° C. and preferably from 150° C. to 450° C. The stream of gaspreferably consists of from 50 to 100 vol % of H₂ and from 0 to 50 vol %of N₂.

If one or more Group Ib, VIIb, or VIIIb metals are to be applied to thesupport in addition to ruthenium or palladium, and if the saidapplication thereof is to take place successively, the support can bedried and optionally calcined between each application or impregnation,the drying temperature ranging from 100° C. to 150° C. and the calciningtemperature being from 200° C. to 600° C. The order in which the metalsalt solutions are applied is arbitrary.

If one or more Group Ib, VIIb, or VIIIb metals are to be applied to thesupport in addition to ruthenium or palladium, it is preferred to useplatinum, copper, rhenium, cobalt, nickel, or mixtures thereof.

The solution of ruthenium salt, palladium salt, or metal salt is appliedto the support(s) at such a rate that the content of active metal isfrom 0.01 to 30 wt %, preferably from 0.01 to 10 wt % and morepreferably from 0.01 to 5 wt %, based on the total weight of thecatalyst, of ruthenium or palladium and optionally of one or more GroupIb, VIIb, or VIIIb metals applied to the support.

The total metal surface area on the catalyst is preferably from 0.01 to10 m²/g and more preferably from 0.05 to 5 m²/g and most preferably from0.05 to 3 m²/g of catalyst. The metal surface area was determined by thechemisorption method, as described in J. Lemaitre et al in“Characterization of Heterogeneous Catalysts”, Ed. Francis Delannay,Marcel Dekker, New York (1984), pp 300-324.

In the catalyst used in the process of the invention the ratio of thesurface area of at least one active metal to that of the catalystsupport is less than approximately 0.3:1, preferably less thanapproximately 0.1:1 and more preferably approximately 0.05:1 or less,the lower limit being approximately 0.0005:1.

SUPPORTS

The support materials used for the preparation of the catalysts to beused in the process of the invention possess macropores and mesopores.The term “macropores” denotes pores having a diamater of more than 50nm, whilst the term “mesopores” relates to pores having a diameterbetween approximately 2.0 nm and approximately 50 nm, as defined in PureApplied Chem. 45,pp 71 et sec, particularly page 79 (1976).

The supports used in the present invention have a pore distribution madeup as follows: from approximately 10 to approximately 50%, preferablyapproximately 15 to approximately 50%, more preferably from 15 to 45%and most preferably from 30 to 40% of the pore volume comprisesmacropores having a pore diameters ranging from approximately 50 nm toapproximately 10,000 nm, whilst approximately 50 to approximately 90%,preferably 50 to approximately 85%, more preferably from 55 toapproximately 85% and most preferably from 60 to approximately 70% ofthe pore volume comprises mesopores having pore diameters ranging from 2to approximately 50 nm, the sum of the pore volumes being 100%.

Preferably, the surface area of the support is from approximately 500m²/g, more preferably from approximately 200 to 350 m²/g and mostpreferably from approximately 200 to approximately 250 m²/g of supportmaterial.

The surface area of the support is determined by the BET method by N₂absorption as specified in DIN 66131. Determination of the average porediameter and the distribution of pore sizes is carried out by Hgporosymmetry, particularly as specified in DIN 66133.

Although, generally, all known catalyst support materials can be used,provided they have the pore size distribution defined above, it ispreferred to use activated charcoal, silicon carbide, aluminum oxide,silicon dioxide, titanium dioxide, zirconium dioxide, magnesium oxide,zinc oxide, or mixtures thereof, more preferably aluminum oxide andzirconium dioxide.

The catalysts used in the present invention show high reactivity (a highturnover index), selectivity, and a long on-stream time. When thecatalysts proposed in the present invention are used for hydrogenationapplications, the hydrogenation products are obtained in high yield andpurity, so that subsequent purification is unnecessary. The conversionis virtually quantitative. Thus the hydrogenation product obtained can,in a preferred embodiment of the present invention, be directly used ina further processing stage, without having to be purified.

Within the hydrogenation of an aromatic compound in which at least onehydroxyl group is bonded to an aromatic ring, in particular within thehydrogenation of 4-alkyl or 4-alkoxy substituted phenols, as describedabove, predominantly trans configurated cycloaliphatic compounds areobtained. The content of trans configurated compounds is according toone embodiment of the present invention at least 60%, preferably atleast 65%. The convertion is essentially quantitative, the content ofresidual aromatics is preferably below 0.01 wt.-%, in relation to thetotal of the produced amount. According to a preferred embodiment of thepresent invention, the obtained hydrogenation product may be directlyintroduced into its further processing stage, without having to bepurified.

SOLVENTS OR DILUENTS

In the process of the invention the reaction, preferably hydrogenation,can be carried out in the absence of a solvent or diluent, i.e. it isnot necessary to carry out the reaction in solution.

It is also possible to directly react the polymer in its melt.

Preferably, however a solvent or diluent is used. The solvents ordiluents used can be any suitable solvents or diluents. The choicethereof is not critical. For example, the solvents or diluents cancontain small amounts of water, if desired.

In the reaction, preferably hydrogenation, of an aromatic compound inwhich at least one hydroxyl group is attached to an aromatic core,examples of suitable solvents or diluents include the following:

Straight-chain or cyclic ethers, such as tetrahydrofuran or dioxane, andalso aliphatic alcohols in which the alkyl radical exhibits preferablyfrom 1 to 10 carbon atoms and more preferably from 3 to 6 carbon atoms.

Examples of alcohols to be preferably used are isopropanol, n-butanol,isobutanol and n-hexanol. Mixtures of these or other solvents ordiluents may also be used.

In the reaction, preferably hydrogenation, of an aromatic compound inwhich at least one amino group is attached to an aromatic core, examplesof suitable solvents or diluents include the following:

Straight-chain or cyclic ethers, such as tetrahydrofuran or dioxane, andalso ammonia and monoalkylamines or dialkylamines in which the alkylradical exhibits preferably from 1 to 3 carbon atoms, such asmethylamine, ethylamine, or propylamine, or the correspondingdialkylamines.

Mixtures of these or other solvents or diluents may also be used.

In both of the above embodiments, the amount of the solvent or diluentused is not subject to particular restrictions and can be freelyselected as required, but those amounts are preferred which produce a 10to 70 wt.-% strength solution of the compound to be hydrogenated.

When carrying out the process of the invention it is particularlypreferred that the product that is formed in the reaction, preferablyhydrogenation of this process be used as solvent, optionally togetherwith other solvents or diluents. In this case a portion of the productthat is formed in the process can be mixed with the compounds to bereacted, preferably hydrogenated. The weight of hydrogenation productadmixed as solvent or diluent is preferably from 1 to 30 times, morepreferably from 5 to 20 times and most preferably from 5 to 10 times theweight of the aromatic compounds to be reacted, preferably hydrogenated.

The above may also be applied for the other compounds which are reactedaccording to the invention. Also in this respect no limitation withregard to the solvent and diluent exists.

In the reaction of polymers examples of suitable solvents or diluentsinclude the following:

hydrocarbons, such as hexane, cyclohexane, methylcyclohexane, heptane,octane, toluene, xylene, etc., and straight-chain or cyclic esters, suchas tetrahydrofurane, dioxane, dibutylether, methyl-tert.-butylether,etc., ketones, such as methyl ethyl ketone and acetone, esters, such asethylacetate, or amides, such as DMF and N-methylpyrrolidon.

Preferably used are cyclohexane, toluene or THF. Mixtures of these andother solvents and diluents may also be used.

If the polymer was obtained by solution polymerization, it is alsopossible to direct react the obtained solution comprising the polymerwithin the process according to the invention.

The amount of the used solvent or diluent is not particularly limitedwithin the process according to the invention and may be freely chosenaccording to demand. However, such amounts are preferred which lead to asolution comprising 1 to 70, preferably 1 to 40 wt.-% of the polymer tobe reacted.

REACTION

In the following the reaction is described by means of a hydrogenationas an example, wherein—in case a dehydrogenation or an oxidation iscarried out—instead of hydrogen or hydrogen-containing gases gaseoushydrocarbons or oxygen-containing gases may be used under thebelow-described conditions.

The hydrogenation is carried out at suitable pressures and temperatures.Pressures above about 2·10⁶ Pa, preferably above 5·10⁶ Pa andparticularly pressures of from about 1·10⁷ to about 3·10⁷ Pa arepreferred. Preferred temperatures range from about 30 to about 250° C.and are preferably about 100 to about 200° C. and particularly about 150to about 200° C.

The hydrogenation process can be carried out continuously or batchwise.When the process is carried out continuously a portion of thehydrogenation product leaving the reactor can be added the reactor feedupstream of the reactor. An portion of the hydrogenation product leavingthe reactor is recycled as solvent, such that the proportions givenunder the heading “Solvents and Diluents” are attained. The remainingamount of hydrogenation product is retrieved.

When the process is carried out continuously the feed rate of thecompound(s) to be hydrogenated is preferably from about 0.05 to about 3kg per liter of catalyst per hour and more preferably from about 0.1 toabout 1 kg per liter of catalyst per hour.

The hydrogenating gases used can be arbitrary gases containing freehydrogen and exhibiting no harmful amounts of catalyst poisons, such asCO. For example, reformer exhaust gases can be used. Pure hydrogen ispreferably used as hydrogenating gas.

In the case of phenols and amines additionally substituted by at leastone optionally substituted C₁-C₁₀ and/or alkoxy radical the isomer ratioof cis-configured to trans-configured products obtained can be variedover a wide range by varying the reaction conditions (temperature,solvents).

If an aromatic compound in which at least one amino group is attached toan aromatic core is to be hydrogenated using the catalyst defined abovethe hydrogenation can also be carried out in the presence of ammonia ordialkylamines, for example methylamine, ethylamine, propylamine ordimethylamine, diethylamine or dipropylamine. Suitable amounts ofammonia or monoalkylamine or dialkylamine are used, these preferablybeing from about 0.5 to about 50 parts by weight, more preferably fromabout 1 to about 20 parts by weight, based, in each case, on 100 partsby weight of the compound(s) to be hydrogenated. Anhydrous ammonia oranhydrous amines are particularly preferably used.

For oxidations generally air or pure oxygen is used. Fordehydrogenations usually carbohydrates, particularly methane or naturalgas, are used.

The invention is described in detail below with reference to someembodiments, where Examples 1 to 4 refer to the hydrogenation of anaromatic compound in which at least one hydroxyl group is attached to anaromatic core, and Examples 5 to 7 relate to the hydrogenation of anaromatic compound in which at least one amino group is attached to anaromatic core. Examples 8 to 12 relate to the reaction of compoundscomprising C═O-groups, and Examples 13 to 16 relate to the reaction ofpolymers.

EXAMPLES

Preparation of Catalyst 1

An aluminum oxide support containing mesopores and macropores and havingthe form of 4 mm extrudates having a surface area (BET) of 238 m²/g anda pore volume of 0.45 ml/g was impregnated with an aqueousruthenium(III) nitrate solution having a concentration of 0.8 wt %. 0.15ml/g (approximately 33% of the total volume) of the pores in the supporthad diameters ranging from 50 nm to 10,000 nm and 0.30 ml/g(approximately 67% of the total pore volume) of the pores in the supporthad diameters ranging from 2 to 50 nm. The volume of solution absorbedby the support during impregnation was approximately equal to the porevolume.

The support impregnated with the ruthenium(III) nitrate solution wasthen dried at 120° C. and activated (reduced) in a stream of hydrogen at200° C. The catalyst thus produced contained 0.05 wt % of ruthenium,based on the weight of the catalyst.

Example 1

A 50 wt.-% strength solution of p-tert-butylphenol was prepared in THF.Then 2500 g/h of this solution were passed with hydrogen at atemperature of 180° C. and an overall pressure of 2.6·10⁷ Pa through aflow reactor, which was packed with 3.2 l of the Ru catalyst describedabove. Following removal of the solvent, by distillation, thehydrogenation product had the following composition:

99.9% of cis,trans-4-tert-butylcyclohexanol

<0.01% of p-tert-butylphenol

Example 2

The hydrogenation was carried out as described in Example 1 except that3500 g of the 50 wt.-% p-tert-butylphenol solution in THF were passedthrough the reactor at a temperature of 200° C. Following distillationof the solvent, the hydrogenation product possessed the followingcomposition:

99.8% of cis,trans-4-tert-butylcyclohexanol

<0.01% of p-tert-butylphenol

Example 3

The hydrogenation was carried out as described in Example 1 except thata 50 wt.-% solution of p-tert-butylphenol in isobutanol was used.Following the distillation of the solvent, the hydrogenation productpossessed the following composition:

67.5% of trans-4-tert-butylcyclohexanol

32.4% of cis-4-tert-butylcyclohexanol

<0.01% of p-tert-butylphenol

Example 4

In an autoclave having a capacity of 3.5 l 2 kg of a solution of 50wt.-% of bisphenol A in THF and 500 ml of the catalyst of Example 1 wereplaced in a catalyst basket. Hydrogenation was then carried out at atemperature of 150° C. and under a pressure of 2·10⁷ Pa over a period offive hours batchwise. The conversion to the desired cycloaliphaticmixture of diol isomers was quantitative, and the residual aromaticscontent was less than 0.01%.

Example 5

1.2 l of the catalyst 1 prepared as described above were packed into anelectrically heated flow reactor. The hydrogenation of aniline was thencommenced under a pressure of 2·10⁷ Pa and at a temperature of 160° C.without previous activation. The hydrogenation was carried outcontinuously in ascending mode, a portion of the hydration effluentbeing recycled via a circulating pump and added to the starting materialupstream of the reactor. The amount of hydrogenation product added assolvent was thus ten times that of the aniline. At the head of theseparator from 500 to 600 l of H₂/h were depressurized. The amount ofaniline that was continuously fed to the reactor corresponded gave aspace velocity of 0.6 kg/l·h.

As a function of reaction temperature the following product compositionswere attained under steady-state reaction conditions:

Temperature CHA¹⁾ DCHA²⁾ Aniline Cyclohexane, + (° C.) (%) (%) (%)Cyclohexane (%) 160 99.1 0.45 0.10 0.04 180 97.0 2.75 0.06 0.06 200 95.93.9 — 009 ¹⁾CHA = cyclohexylamine; ²⁾DCHA = dicyclohexylamine

Example 6

The hydrogenation was carried out as described in Example 5 except thatadditionally anhydrous ammonia was continuously metered in. Based on 100wt.-% of aniline 10 parts by weight of ammonia were added. As a functionof reaction temperature the following product compositions were attainedunder steady-state reaction conditions:

Temperature CHA¹⁾ DCHA²⁾ Aniline Cyclohexane + (° C.) (%) (%) (%)Cyclohexane 180 99.3 0.08 — 0.07 200 98.4 0.8 — 0.09 ¹⁾CHA =cyclohexylamine; ²⁾DCHA = dicyclohexylamine

Example 7

In an autoclave having a capacity of 3.5 l there were placed 2 kg of asolution of 50 wt.-% of toluylene diamine (mixture of2.4-;2.6-diaminotoluene isomers) in THF and 500 ml of the catalyst thatwas described above. Hydrogenation was then carried out at a temperatureof 150° C. and under a pressure of 2·10⁷ Pa over a period of five hoursbatchwise. The conversion to the desired cycloaliphatic mixture ofdiamine isomers was quantitative, and the residual aromatics content wasless than 0.01%.

Example 8

3 l of catalyst 1 were introduced into a tube reactor (length=2500 nm,dia=45 nm). Subsequently, the reactor was filled with n-butanol and washeated to 180° C. at a hydrogen pressure of 3·10⁶ Pa (30 bar). Then, anamount of 1 kg/h n-butylalderhyde was continuously introduced into thereactor with a flow amount of 50 l/h. The obtained reaction product wascolorless and free from ruthenium.

A conversion of 99.4% and a selectivity with respect to n-butanol of99.7, respectively based on the introduced amount of n-butylalderhyde,was determined by gas chromotagraphic evaluation.

Example 9

3 l of catalyst 1, 700 g of a copolymer of ethylene and CO (M_(w) 5000,CO content 35% percent), dissolved in 1300 g THF, were introduced in a3.5 l-autoclav.

Subsequently, the mixture was hydrogenated at 180° C. and 2·10⁷ Pa (200bar) hydrogen pressure for 5 hours. The conversions to the desiredpolyalcohol was 93%, based on the introduced amount of the copolymer.

Example 10

3 l of catalyst 1 were introduced into a 3.5 l-autoclav, and 2000 gbenzaldehyde were introduced there into. Subsequently the mixture washydrogenated at 180° C. and 2·10⁷ Pa (200 bar) hydrogen pressure for 10hours. The conversion to the desired cyclohexyl methanol was 100% at aselectivity of 96.5%, based on the introduced amount of benzaldehyde,respectively.

Example 11

3 l of catalyst 1 were introduced into a 3.5 l-autoclav, and 2000 g2-ethylhexanaol were introduced there into. Subsequently, the mixturewas hydrogenated at 180° C. and 2·10⁷ Pa (200 bar) hydrogen pressure for10 hours. The conversion to the desired 2-ethylhexanol was 100% at aselectivity of 97.2%, based on the introduced amount of 2-ethylhexanol,respectively.

Example 12

In a 0.3 l-stirring autoclav, 100 ml adipodimethylester was reacted atcatalyst 1. The mixture was stirred for 12 hours at a hydrogen pressureof 2·10⁷ Pa (200 bar) and a temperature of 220° C. A conversion of 98%and a yield with respect to hexandiol of 91% based on the introducedamount of adipodimethylester was determined by a gaschromatic analysisof the obtained product.

Preparation of Catalyst 2

An aluminum oxide support containing mesopores and macropores and havingthe form of 4 mm extrudates having a surface area (BET) of 238 m²/g anda pore volume of 0.45 ml/g was impregnated with an aqueouspalladium(III) nitrate solution having a concentration of 0.8 wt %. 0.15ml/g (approximately 33% of the total volume) of the pores in the supporthad diameters ranging from 50 nm to 10,000 nm and 0.30 ml/g(approximately 67% of the total pore volume) of the pores in the supporthad diameters ranging from 2 to 50 nm. The volume of solution absorbedby the support during impregnation was approximately equal to the porevolume.

The support impregnated with the palladium(III) nitrate solution wasthen dried at 120° C. and activated (reduced) in a stream of hydrogen at200° C. The catalyst thus produced contained 0.05 wt % of palladium,based on the weight of the catalyst.

Example 13

2 kg of a solution of 25 wt % of a triblockpoly(styrene-co-butadiene-co-styrene) having a molecular weight of300,000 (weight average) in cyclohexane and 500 ml of catalyst 1described above (0.5 wt % of Ru/Al₂O₃, ratio of metallic surface area tosupport surface area 0.001:1) were placed in an autoclave having acapacity of 3.5 l.

Hydrogenation was then carried out batchwise over a period of five hoursat 100° C. and under a pressure of 1×10⁷ Pa. The content of hydrogenatedmaterial in the polymer was 95%, and the aromatic content was the sameas in the starting polymer. There was no reduction in molecular weight.

Example 14

2 kg of a solution of 50 wt % of polybutadiene having a molecular weightof 6,000 (weight average) in cyclohexane and 500 ml of catalyst 1described above were placed in an autoclave having a capacity of 3.5 l.Hydrogenation was then carried out batchwise over a period of five hoursat 100° C. and under a pressure of 1×10⁷ Pa. The conversion content ofhydrogenated material in the to the desired polymer was quantitative.There was no reduction in molecular weight.

Example 15

2 kg of a solution of 25 wt % of a poly(acrylonitrile-co-butadiene)having a molecular weight of 30,000 (weight average) in tetrahydrofuranand 500 ml of catalyst 1 described above were placed in an autoclavehaving a capacity of 3.5 l. Hydrogenation was then carried out batchwiseover a period of five hours at 180° C. and under a pressure of 1×10⁷ Pa.The content of hydrogenated material in the polymer was 92%, The nitrilecontent was 85% of that in the starting polymer. There was no reductionin molecular weight.

Example 16

2 kg of a solution of 25 wt % of a triblockpoly(styrene-co-butadiene-co-styrene) having a molecular weight of300,000 (weight average) in cyclohexane and 500 ml of catalyst 2 (0.5%of Pd/Al₂O₃) described above were placed in an autoclave having acapacity of 3.5 l.

Hydrogenation was then carried out batchwise over a period of five hoursat 100° C. and under a pressure of 1×10⁷ Pa. The conversion to thedesired partially saturated polymer was 97%, and the aromatic contentwas 94% of that in the starting polymer. There was no reduction inmolecular weight.

We claim:
 1. A process for preparing an organic compound by catalytichydrogenation, which process comprises reacting an organic compound inthe presence of a catalyst; said organic compound being selected fromthe group consisting of an aromatic compound in which at least onehydroxyl group is bonded to an aromatic ring, an aromatic compound inwhich at least one amino group is bonded to an aromatic ring, or amixture of two or more of these organic compounds; said catalystcomprising ruthenium or ruthenium together with at least one Group Ib,VIIb or VIIIb metal, in an amount of from 0.01 to 30 wt %, based on thetotal weight of the catalyst; said catalyst being applied to a catalystsupport having a pore volume and a surface area (BET) of from 50 to 500m²/g; wherein from 10 to 50% of the pore volume of the catalyst supportcomprises macropores having a pore diameter of from 50 nm to 10,000 nm;and wherein from 50 to 90% of the pore volume of the support comprisesmesopores having a pore diameter of from 2 to 50 nm, the sum of saidpore volumes being 100%.
 2. The process of claim 1 in which the ratio ofthe surface area of the metal catalyst to the surface area (BET) of thecatalyst support is from 0.0005:1 to 0.3:1.
 3. The process of claim 1 inwhich the Group Ib, VIIb and VIIIb metal is selected from the groupconsisting of platinum, cobalt, copper, rhenium and nickel, or a mixtureof to or more of these metals.
 4. The process of claim 1 in which thecatalyst support is selected from the group consisting of activatedcharcoal, silicon carbide, aluminum oxide, silicon dioxide, titaniumdioxide, zirconium dioxide, magnesium dioxide and zinc oxide, or amixture of two or more thereof.
 5. The process of claim 1 in which thereaction is carried out in the presence of a solvent or diluent.
 6. Theprocess of claim 1 in which the organic compound is an aromatic compoundin which at least one amino group is bonded to an aromatic ring.
 7. Theprocess of claim 1 in which the organic compound is an aromatic compoundin which at least one hydroxyl group is bonded to an aromatic ring.